/*
* This program is free software; you can redistribute it and/or modify it under the terms of
* the GNU AFFERO GENERAL PUBLIC LICENSE as published by the Free Software Foundation; either version 3 of the License,
* or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU AFFERO GENERAL PUBLIC LICENSE for more details.
* You should have received a copy of the GNU AFFERO GENERAL PUBLIC LICENSE along with this program;
* if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
package com.meidusa.amoeba.parser.expression;
/**
*
* @author <a href=mailto:piratebase@sina.com>Struct chen</a>
*
*/
public class ParameterExpression extends Expression {
private int index;
public ParameterExpression(int index){
this.index = index;
}
@SuppressWarnings("unchecked")
@Override
public Comparable evaluate(Object[] parameters) {
if(parameters == null || parameters.length ==0){
return null;
}
if(parameters[index] instanceof Comparable){
return (Comparable)parameters[index];
}else if(parameters[index] instanceof byte[]){
return new String((byte[])parameters[index]);
}else{
return parameters[index]==null?null:parameters[index].toString();
}
}
public boolean isRealtime(){
return true;
}
@Override
public Expression reverse() {
return this;
}
@Override
protected void toString(StringBuilder builder) {
builder.append("?");
}
}